I used to live in Nam, and yes, the friction becomes slippery when really hot. That place can get 40 degrees regularly, so what Justin said. You don't want to get stuck 9m above your last draw (some routes are seriously run out, typical granite style)... Granite falls can be BAAAADDDD! Take a lever-biner or mailon just in case. And a pair of Prussic cords per harness - never multy-pitch without them!